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Behavior & Limits

Supported platforms, lifecycle guarantees, and limits for Alien Daemons.

Guarantees

Resident process. A daemon is started and kept running by the platform controller. If it exits, the underlying Local or Kubernetes runtime is responsible for restart behavior.

No request-response API. Daemon has no invocation API, timeout, or trigger model. Public endpoints are optional HTTP routing surfaces, not invocation semantics.

Command-capable when enabled. If commandsEnabled is true, the daemon runtime can poll the manager and execute registered command handlers.

Cloud controllers. AWS, GCP, and Azure daemon resources run on the managed compute plane and can attach managed HTTP endpoints.

Limits

LimitValueNotes
Supported platformsAWS, GCP, Azure, Local, KubernetesController behavior is platform-specific.
Replicas1 on KubernetesDaemon currently maps to a single-replica Deployment.
Public endpointsHTTP onlyAdd named endpoints explicitly.
TriggersNot supportedUse Worker for queue, storage, schedule, or HTTP-triggered work.
Direct invocationNot supportedUse Worker for request-response calls.
Source daemons on LocalNot supported by the controllerUse a container image.
Source daemons on KubernetesNot supported by the controllerUse a container image.
CommandsDisabled by defaultEnable explicitly with .commandsEnabled(true).

Platform Notes

Local

  • The controller extracts the daemon container image, starts it through the local runtime manager, and checks health every 5 seconds while ready.
  • Linked resource bindings and standard Alien environment variables are injected into the process environment.
  • Delete stops and removes the local daemon process state.

Kubernetes / On-Prem

  • The controller creates a Kubernetes Deployment with one replica.
  • The pod restart policy is Always.
  • Linked resource bindings are injected as environment variables. Secret values are moved into Kubernetes Secrets where the binding extraction code supports it.
  • The current controller rejects source-based daemon config; deploy an image.

AWS, GCP, Azure

  • Daemons run on the managed compute plane.
  • Public endpoints use provider load balancing and managed DNS when configured.
  • Omit public endpoints for private background processes.
  • Managed clustered daemons receive generic topology hints in ALIEN_DAEMON_PRIVATE_ADDRESS, ALIEN_DAEMON_PEER_PRIVATE_ADDRESSES, and ALIEN_DAEMON_NODE_COUNT. Treat these as application-level hints; Alien owns the underlying private network implementation.

Design Decisions

Daemon is process supervision, not a scalable service abstraction. It has no triggers, scaling, or storage model. Use Container when you need replica controls, persistent storage, or multiple service ports.

Commands are opt-in. A daemon without command handlers should not poll the manager for work.

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